Probiotics, gut-friendly bacteria that benefit the host, are in the spotlight, No wonder! Your gut is swarming with trillions of tiny bacteria that impact everything from how your body digests food to brain health and immune health. Yet these tiny critters are only part of the story. Bacteria need food to live, and we don’t focus enough on the food they feed on called prebiotics. They are components that support a healthy gut microbiome and you get them through diet.
Sometimes people confuse the two terms or think prebiotics and probiotics are variations of the same thing. However, prebiotics is a type of fiber that your body can’t break down, but bacteria can. When the fiber passes into your intestines, since it wasn’t absorbed, gut bacteria feast on it. When these tiny organisms munch on fiber, they produce short-chain fatty acids that help keep the lining of your colon healthy.
Prebiotics may play a role in weight control and weight loss too. In fact, research shows that obese people have a different microbiome composition than normal-weight individuals. Probiotics, the actual gut bacteria that prebiotics munch on, may impact body weight in several ways. For example, research shows that some gut bacteria reduce fat absorption, and therefore the total calories you absorb from a meal. The composition of your gut microbiome also impacts hormones that control satiety. One study found that gut microbiome composition affects a protein called ANGPTL4 that reduces how much body fat a person stores around their waist, hips, and other sites.
Therefore, there is some evidence that probiotics play a role in how much a person weighs, but what about prebiotics (the food that gut bacteria dine on)? There’s some evidence that prebiotics help with weight loss and weight control too. One way they help curb weight gain is by suppressing appetite. After all, prebiotics is a type of fiber and fiber slows digestion and helps reduce appetite. Can consuming a prebiotic supplement help you trim your waistline and lose body fat?
According to Professor Robert Hutkins, a scientist who studies prebiotics and probiotics at the University of Nebraska, animal studies show that prebiotics increase satiety and reduce the number of calories that animals eat. The evidence that prebiotics have a similar benefit in humans is less clear, mostly because there aren’t many studies looking at this issue. However, one human study found that taking a 16-gram prebiotic supplement each day increased the release of gut peptides that suppress appetite.
Another study found that subjects who munched on prebiotic-rich vegetables felt more satiated and satisfied. They also had fewer cravings for sweet foods. That’s a bonus for people who have a hard time keeping sweet stuff off their plates!
But who wants to take a prebiotic supplement every day? Unless there’s clear evidence that a supplement is better, it’s best to get nutritional components from food sources. What are the best food sources of prebiotics?
Prebiotics are a type of soluble fiber, meaning they dissolve in water. In contrast, insoluble fiber, the type that helps with bowel movements, is called insoluble fiber because it isn’t water-soluble. Prebiotics are also fermentable, meaning bacteria can metabolism the fiber and produce short-chain fatty acids beneficial to the gut. Some examples are foods high in oligosaccharides and inulin. Specific foods that stand out in this respect include onions, leeks, Jerusalem artichokes, garlic, legumes, apples, asparagus, and bananas.
Chances are, you already eat some of these foods, and you can add more prebiotics to your diet by making small changes. For example, toss dandelion greens into your next salad. This dark, leafy green is rich in a prebiotic fiber called inulin. Dandelion greens are also a rich source of anti-inflammatory compounds. In fact, adding them to a salad is a great way to boost the prebiotic content of your diet. Add onions, leeks, artichokes, asparagus, and chunks of apples for a prebiotic-rich salad that tastes delicious too. These foods offer an abundance of vitamins, minerals, and phytonutrients for an extra burst of nutrients.
A Word of Caution
When you increase the prebiotic content of your diet, do it slowly. It takes time for your intestinal tract to adapt to an increase in fiber. Plus, if you have irritable bowel syndrome (IBS), prebiotic foods can worsen bloating, diarrhea, cramping, and other IBS symptoms. Studies show that some people with IBS are sensitive to a type of fermentable carbohydrates called FODMAPs. In fact, a study published in Gastroenterology found that 75% of IBS sufferers reduced their symptoms when they eliminated FODMAPs from their diet. You can find a list of foods high in FODMAPs on a number of sites. If you have IBS, try eliminating these foods and see if your symptoms improve. Otherwise, adding more prebiotic fiber to your diet should have positive benefits for your health and gut microbiome. There’s a fiber shortfall! Most Americans only consume about half the fiber they need for good health.
The Bottom Line
There’s still more to learn about the microbiome and the prebiotics its residents feed on. At the very least, the high fiber content of prebiotic-rich foods should help you feel fuller and more satisfied. If you also enjoy fermented foods, like yogurt with active cultures, kefir, miso, and fermented vegetables, such as fresh sauerkraut, you’ll supply your gut with a diversity of probiotics too. The two work together to create intestinal harmony. Beyond weight loss, they may help create a more balanced immune system too since 70% of your immune system is in your gut. So, take advantage of the benefits prebiotic-rich foods offer. You could be rewarded with a trimmer waistline!
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